Angular x-ray cross-correlation analysis (AXCCA): Basic concepts and recent applications to soft matter and nanomaterials

TL;DR

AXCCA is a powerful x-ray analysis technique that quantifies angular anisotropy and orientational order in soft matter and nanomaterials, with recent advances involving micro- and nanofocused x-ray microscopy.

Contribution

This review introduces AXCCA and surveys recent experimental applications in soft matter systems using advanced x-ray microscopy techniques.

Findings

AXCCA effectively measures angular anisotropy in various soft matter systems.

Recent applications demonstrate the technique's capability with micro- and nanofocused x-ray microscopy.

AXCCA provides detailed insights into the orientational order of complex materials.

Abstract

Angular x-ray cross-correlation analysis (AXCCA) is a technique which allows quantitative measurement of the angular anisotropy of x-ray diffraction patterns and provides insights into the orientational order in the system under investigation. This method is based on the evaluation of the angular cross-correlation function of the scattered intensity distribution on a two-dimensional (2D) detector and further averaging over many diffraction patterns for enhancement of the anisotropic signal. Over the last decade, AXCCA was successfully used to study the anisotropy in various soft matter systems, such as solutions of anisometric particles, liquid crystals, colloidal crystals, superlattices composed by nanoparticles, etc. This review provides an introduction to the technique and gives a survey of the recent experimental work in which AXCCA in combination with micro- or nanofocused x-ray microscopy was used to study the orientational order in various soft matter systems.